Low-grade inflammation plays a pivotal role in gastrointestinal dysfunction in irritable bowel syndrome

Table 1 Rome III criteria

Recurrent abdominal pain or discomfort for at least 3 d per month in the last 3 mo associated with two or more of the following

Improvement with defecation

Onset associated with a change in frequency of stool

Onset associated with a change in form (appearance) of stool

Table 2 Immune cells and mediators affecting gastrointestinal motility

Immune cells/mediators	Muscle contractility	Ref.
Macrophage	↑→	[59,60]
T cell	↑↓	[57,61-64,72]
Proinflammatory cytokines; IL-1β, IL-6, TNFα	↓	[62,66-68,70]
Th1 cytokines; IFNγ, IL-12	↓	[69,75]
Th2 cytokines; IL-4, IL-9, IL-13	↑	[60,71-74]
Th17 cytokines; IL-17	↑	[87,88]
Th1/Th2 balance; Th1 > Th2	↓	[79,80]
Th1 < Th2	↑	[61,79,80]
5-HT	↑	[17,20,27,28,80]
MAP kinase	↑	[56,61]
CPI-17	↓	[62]
L type Ca2+ channel	↓	[70]

TNF: tumor necrosis factor; IFN: interferon; IL: interleukin; 5-HT: serotonin; MAP: mitogen activated protein; CPI-17: protein kinase C-potentiated phosphatase inhibitor protein-17 kDa; Ref: references.